>> /usr/share/fonts/google-noto-serif-cjk-vf-fonts/NotoSerifCJK-VF.ttc
>
> I see, thanks. Alas, this is actually another bug in FontConfig; it
> doesn't properly handle Font Variations in TTCs. I've reported it
> just now as
>
> https://gitlab.freedesktop.org/fontconfig/fontconfig/-/issues/488
After some more thinking I now believe that this is a bug in LilyPond.
My understanding is that function `link-ps-resdir-font` in
`framework-ps.scm` has to be adjusted – it should accept Font
Variations that don't access the variation part but only the default
instance (which is 'NotoSerifCJKjp-ExtraLight' for the font in
question).
Masamichi-san, please have a look!
Werner